Degradation of aromatic hydrocarbons by white‐rot fungi in a historically contaminated soil

Abstract

Phanerochaete chrysosporium NRRL 6361 and Pleurotus pulmonarius CBS 664.97 were tested for their ability to grow under nonsterile conditions and to degrade various aromatic hydrocarbons in an aged contaminated soil that also contained high concentrations of heavy metals. After 24 days fungal incubation, carbon-CO2 liberated, an indicator of microbial activity, reached a plateau. At the end of the incubation time (30 days), fungal colonization was clearly visible and was confirmed by ergosterol and cell organic carbon determinations. In spite of unfavorable pH (around 7.4) and the presence of heavy metals, both fungi produced Mn-peroxidase activity. In contrast, laccase and aryl-alcohol oxidase were detected only in the soil treated with P. pulmonarius CBS 664.97 and lignin-peroxidase in that with P. chrysosporium NRRL 6361. No lignin-modifying enzyme activities were present in non-inoculated soil incubated for 30 days (control microcosm). Regardless of the fungus employed, a total removal of naphtalene, tetrachlorobenzene, and dichloroaniline isomers, diphenylether and N-phenyl-1-naphtalenamine, was observed. Significant release of chloride ions was also observed in fungal-treated soil, in comparison with that recorded in the control microcosm. Both fungi led to a significant decrease in soil toxicity, as assessed using two different soil contact assays, including the Lepidium sativum L. germination test and the Collembola mortality test.

Investigation of growth responses in saprophytic fungi to charred biomass

“…Furthermore, the ability of these fungi to co-metabolise a range of macromolecules from polycyclic aromatic hydrocarbons (PAHs) and pentachlorophenols (PCPs) to tars and oils has also been reported [21,22,23,24].…”

Extracellular Ligninolytic Enzymes in Bjerkandera adusta and Lentinus squarrosulus

“…Mushrooms are cultured world wide for their taste, nutritional attributes and potential applications in industries [1]. In addition, they have many medicinal uses and are good agents of bioremediation [2,3].…”

Effective degradation of organic pollutants in aqueous media by microbial strains isolated from soil of a contaminated industrial site

“…The fungi exude copiously organic acids and oxidative enzymes from their mycelia, thus contributing to biodegrade organic contaminants in soil. In particular, white-rot basidiomycetes species such as Pleurotus ostreatus and Trametes versicolor co-metabolically degrade toxic compounds, such as PAH, by a considerable production of ligninolytic enzymes [22][23][24][25]. Nevertheless, even non-ligninolytic fungi such as Aspergillus niger are reported to oxidize a variety of PAH, including chrysene and benzo(a)pyrene, by an intracellular cytochrome P-450 dependent oxidase system [26].…”